Vehicle apparatuses with electronic components for road toll systems, so-called “onboard-units” (OBUs), are currently supplied with power by batteries that represent the largest component of such an OBU. Although the power consumption of an OBU lies in the range of micro watts (μW) and therefore is extremely low, the required service life of an OBU of more than 5 years results in a battery capacity of 100 mAh or greater, which requires that the batteries have a corresponding size.